Deck Marking & Layout
Marking and layout is the third step in building your deck. The layout is possibly the most important step after you have made
the decision to proceed. The placement of the footings is critical to the location of the support posts, which will ultimately make
your deck a safe and enjoyable place to enjoy the outdoors, and keep it from falling down!
Even though there is room for error in measuring the location of the footings, success comes from striving for accuracy--
measure to the 1/8th of an inch. This layout is simple and can easily be completed by any level of DIYer. Mistakes can be
corrected at a later part of the project if necessary. These mistakes however, will add time and money to your deck project if
To set up for this task, gather your drawings, tape measure, marking tools, level, all of your equipment, and put them on a site
worktable for easy reference and a place to find them. A paperweight of tools and other heavy objects will keep the plans in
place if the wind begins to blow.
Time to complete this project depends on the size of the deck and the level of help available, the times listed here are for two
people on a 10'x 30' deck with the house defining two sides of the deck.
• Beginner - 3 hours
• Intermediate - 2 hours
• Advanced - 1 hours
Check for hidden utility lines before you start.
Check local code restrictions to be sure that you comply with their regulations on deck height off the ground and
limitations on the amount of lot coverage allowed.
Rushing the layout can cause the deck to be built out of quot;squarequot; which will make the final placement of
deck boards and hand railings extremely difficult at the end of the project.
A helper who understands the overall design and layout process will be invaluable in holding the dummy end
of the tape and helping to line up marking strings.
1. Your first measurements and marking indicate where your deck connects to the house. After
the height of the deck is marked, move away from the house to locate the remaining deck
supports. Your measurements should take into account that the deck is an outdoor
extension of your indoor living space, and needs to slope away from the house to allow any
water that collects on the deck to drain away from the house and the foundation of your
2. Begin by marking the top of the ledger, the structural deck support that will attach to your
house, in several locations. Use your level to verify that the top of the ledger matches your
structural drawing. Keep in mind that if your finished deck surface is 2x material, the top of
the ledger will be 1½quot; below the finished height of the deck as most 2x decking material is
actually 1½quot;. Repeat this step on all walls that join the deck. Note: The drainage slope on
the deck will show on any adjacent deck wall markings.
3. Now we will mark the outside perimeter of the deck foundation where the deck will be
supported from the ground as indicated on your construction drawing. To establish this line,
take two equal measurements, in separate locations, from the longest parallel house wall as
shown, and mark the location with the nylon line. These measurements should indicate the
centerline of the post base. The string line(s) should be directly over the center of the post
base. Be sure that you keep the measurements parallel to each other and perpendicular
(square) to the wall.
4. The string line can be attached at the ledger location with a nail or screw at one end and
tied around a stake driven into the ground at the other end. Be sure to drive the stake
quot;outsidequot; the deck perimeter so it can stay in place until the support posts are set. Be sure
to keep the string line above the top of the ledger height if possible so the footings can be
dug, the concrete can be poured, and the vertical support posts can be placed, without
5. Measure the distance from any adjacent walls to locate adjacent sides of the deck (post
base) and mark with nylon line the same way as in step 2. Remember to keep the
6. Layout any interior post bases using the same technique as the perimeter using two equal
measurements and marking them with a string line.
7. The grid formed by the nylon line should be the same as the grid on your plans showing the
structural members (girders) which will in turn support the joists, which support the finished
deck boards. The intersection of the string lines indicates the center of the post bases.
8. Be sure to check your layout for square using the 3-4-5 right triangle method. Or you can
check for square by measuring from opposite corners and comparing the dimensions, they
should be equal: within 3/8 inch will be acceptable on this project In the next tutorial we
will be pouring concrete in the post bases and attaching the ledger board to the house.
• 24quot; to 30quot; stakes. (Use 1x2 wood or metal stakes) Two stakes per corner
• 16d nails
• 25' tape measure
• Carpenters pencil or a permanent marker
• 100' quot;reelquot; tape, or longer if the diagonal measurement is greater than 100'
• 500' of nylon line (this quot;stringquot; comes in highly visible colors and is good for laying out piers and footings for any
• Water level, string level or some other tool to find level.